Index: errors.hpp
===================================================================
--- errors.hpp	(Revision 79163)
+++ errors.hpp	(Arbeitskopie)
@@ -250,7 +250,7 @@
         }
 
         /** Does NOT set option name, because no option name makes sense */
-        virtual void set_option_name(const std::string& option_name){}
+        virtual void set_option_name(const std::string& /* option_name */){}
 
         ~error_with_no_option_name() throw() {}
     };